枚举属性谓词-Swift

Question

i have an array of Section objects

class Section: NSObject {

    enum SectionType : String {
        case Name = "NAME"
        case Address = "ADDRESS"
        case Phone = "PHONE"
    }
    var type : SectionType = .Name
} 

i need to apply predicate on type property

let predicate = NSPredicate(format: "SELF.type == %d", SectionType.Name.rawValue)
let filteredArray = (preferenceSections as NSArray).filteredArrayUsingPredicate(predicate) //CRASH 
if filteredArray.count > 0 {

}

App is crashing with Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<Mobile.Section 0x7fb120d33c50> valueForUndefinedKey:]: this class is not key value coding-compliant for the key type.' , but the section object has type property, which is enum of string.

Please help me fixing the issue

Answer 1

The error message says it all. There's no mapping from your enum type to an Objective-C type, which means the property isn't "key value coding-compliant." You'd need to use a simpler enum : Int type for this to map automatically.

Answer 2

use "%@" instead "%d".

let predicate = NSPredicate(format: "SELF.type == %@", SectionType.Name.rawValue)